i have a 520m sport and the fookin dash is always tellin g me their is something or other wrong lol.nice cars but does nothing for me tbh the wife uses it and loves it though
ive been told to remove the small blue wire from the battery as it tells the ecu if the battery is down any little bit and the car wont start even though the battery would be well able to start the car.
on replacing a battery as long as the battery is the same or better than whats in it ,the battery doesnt have to be registered to the ecu .